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1.
Radiol Case Rep ; 19(11): 5071-5077, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39253046

RESUMO

Postoperative pancreatic fistula, a significant complication following pancreaticoduodenectomy, can lead to the development of pseudoaneurysms, which in turn can result in hemorrhagic and septic complications. Here, we present the case of a 67-year-old male patient diagnosed with pancreatic head carcinoma who underwent partial pancreatectomy. Ten days postsurgery, the patient experienced hemorrhagic shock due to intraperitoneal bleeding. Emergency exploratory laparotomy and implantation of a stent in the common hepatic artery successfully stopped the bleeding. However, the patient later developed gastrointestinal bleeding, and no apparent source was detected during endoscopic examination. Two complex transcatheter arterial embolization procedures were performed, successfully stopping the bleeding. It is crucial to consider pseudoaneurysm in cases of suspected biliary and pancreatic leakage. This case also underscores the importance of a thorough vascular assessment prior to placing a coated stent, to prevent postoperative obstruction of catheter access to the responsible vessel. Additionally, embolization via the external path of the stent proved feasible.

3.
Front Oncol ; 13: 1174069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37182122

RESUMO

Objectives: We aimed to construct and validate a radiomics-based nomogram model derived from gadoxetic acid-enhanced magnetic resonance (MR) images to predict cytokeratin (CK) 19-positive (+) hepatocellular carcinoma (HCC) and patients' prognosis. Methods: A two-center and time-independent cohort of 311 patients were retrospectively enrolled (training cohort, n = 168; internal validation cohort, n = 72; external validation cohort, n = 71). A total of 2286 radiomic features were extracted from multisequence MR images with the uAI Research Portal (uRP), and a radiomic feature model was established. A combined model was established by incorporating the clinic-radiological features and the fusion radiomics signature using logistic regression analysis. Receiver operating characteristic curve (ROC) was used to evaluate the predictive efficacy of these models. Kaplan-Meier survival analysis was used to assess 1-year and 2-year progression-free survival (PFS) and overall survival (OS) in the cohort. Results: By combining radiomic features extracted in DWI phase, arterial phase, venous and delay phase, the fusion radiomics signature achieved AUCs of 0.865, 0.824, and 0.781 in the training, internal, and external validation cohorts. The final combined clinic-radiological model showed higher AUC values in the three datasets compared with the fusion radiomics model. The nomogram based on the combined model showed satisfactory prediction performance in the training (C-index, 0.914), internal (C-index, 0.855), and external validation (C-index, 0.795) cohort. The 1-year and 2-year PFS and OS of the patients in the CK19+ group were 76% and 73%, and 78% and 68%, respectively. The 1-year and 2-year PFS and OS of the patients in the CK19-negative (-) group were 81% and 77%, and 80% and 74%, respectively. Kaplan-Meier survival analysis showed no significant differences in 1-year PFS and OS between the groups (P = 0.273 and 0.290), but it did show differences in 2-year PFS and OS between the groups (P = 0.032 and 0.040). Both PFS and OS were lower in CK19+ patients. Conclusion: The combined model based on clinic-radiological radiomics features can be used for predicting CK19+ HCC noninvasively to assist in the development of personalized treatment.

4.
Cancer Biol Ther ; 19(12): 1174-1184, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30067431

RESUMO

Oncolytic adenoviruses (Ads) are cancer selective tumoricidal agents; however their mechanism of Ad-mediated cancer cell lysis, or oncolysis, remains undefined. This report focuses upon the autophagy mediator c-JUN n-terminal kinase (JNK) and its effects upon Ad oncolysis and replication. Previously, E1b-deleted Ads have been used to treat several hundred cancer patients with limited clinical efficacy. We hypothesize that by studying the potential interactions between E1b and JNK, mechanisms to improve oncolytic Ad design and cancer therapeutic efficacy may be elucidated. To test this hypothesis, E1b was selectively deleted from the Ad genome. These studies indicated that Ads encoding E1b induced JNK phosphorylation predominately occurred via E1b-19K. The expression of another crucial Ad gene E1a was then overexpressed by the CMV promoter via the replication competent Ad vector Adhz69; these data indicated that E1A also induced JNK phosphorylation. To assess the effects of host cell JNK expression upon Ad oncolysis and replication, siRNA targeting JNK1 and JNK2 (JNK1/2) were utilized. The oncolysis and replication of the E1b-19K wild-type Ads Ad5 and Adhz63 were significantly attenuated following JNK1/2 siRNA transfection. However the oncolytic effects and replication of the E1b-19K deleted Ad Adhz60 were not altered by JNK1/2 siRNA transfection, further implicating the crucial role of E1b-19K for Ad oncolysis and replication via JNK phosphorylation. This study has demonstrated for the first time that JNK is an intriguing molecular marker associated with enhanced Ad virotherapy efficacy, influencing future Ad vector design.


Assuntos
Adenoviridae , Vetores Genéticos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias/metabolismo , Terapia Viral Oncolítica , Vírus Oncolíticos , Replicação Viral , Adenoviridae/genética , Proteínas E1B de Adenovirus/genética , Proteínas E1B de Adenovirus/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Interações Hospedeiro-Patógeno , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Camundongos , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Fosforilação , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Viruses ; 8(12)2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27999391

RESUMO

Adenoviruses (Ads) have been extensively manipulated for the development of cancer selective replication, leading to cancer cell death or oncolysis. Clinical studies using E1-modified oncolytic Ads have shown that this therapeutic platform was safe, but with limited efficacy, indicating the necessity of targeting other viral genes for manipulation. To improve the therapeutic efficacy of oncolytic Ads, we treated the entire Ad genome repeatedly with UV-light and have isolated AdUV which efficiently lyses cancer cells as reported previously (Wechman, S. L. et al. Development of an Oncolytic Adenovirus with Enhanced Spread Ability through Repeated UV Irradiation and Cancer Selection. Viruses2016, 8, 6). In this report, we show that no mutations were observed in the early genes (E1 or E4) of AdUV while several mutations were observed within the Ad late genes which have structural or viral DNA packaging functions. This study also reported the increased release of AdUV from cancer cells. In this study, we found that AdUV inhibits tumor growth following intratumoral injection. These results indicate the potentially significant role of the viral late genes, in particular the DNA packaging genes, to enhance Ad oncolysis.


Assuntos
Adenoviridae/genética , Adenoviridae/fisiologia , Empacotamento do DNA , Mutação , Vírus Oncolíticos/genética , Vírus Oncolíticos/fisiologia , Liberação de Vírus , Adenoviridae/efeitos da radiação , Análise Mutacional de DNA , Vírus Oncolíticos/efeitos da radiação , Raios Ultravioleta , Proteínas Virais/genética
6.
Virology ; 487: 249-59, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26561948

RESUMO

Oncolytic adenoviruses (OAds) are very promising for the treatment of lung cancer. However, OAd-based monotherapeutics have not been effective during clinical trials. Therefore, the effectiveness of virotherapy must be enhanced by combining OAds with other therapies. In this study, the therapeutic potential of OAd in combination with temozolomide (TMZ) was evaluated in lung cancer cells in vitro and in vivo. The combination of OAd and TMZ therapy synergistically enhanced cancer cell death; this enhanced cancer cell death may be explained via three related mechanisms: apoptosis, virus replication, and autophagy. Autophagy inhibition partially protected cancer cells from this combined therapy. This combination significantly suppressed the growth of subcutaneous H441 lung cancer xenograft tumors in athymic nude mice. In this study, we have provided an experimental rationale to test OAds in combination with TMZ in a lung cancer clinical trial.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Apoptose/efeitos dos fármacos , Dacarbazina/análogos & derivados , Neoplasias Pulmonares/terapia , Terapia Viral Oncolítica/métodos , Adenoviridae/fisiologia , Infecções por Adenoviridae/virologia , Proteínas E1B de Adenovirus/genética , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Terapia Combinada/métodos , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Dacarbazina/uso terapêutico , Células HEK293 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Vírus Oncolíticos/fisiologia , Temozolomida , Proteínas Supressoras de Tumor/metabolismo , Replicação Viral , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
7.
Viruses ; 7(11): 5767-79, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26561828

RESUMO

Various viruses have been studied and developed for oncolytic virotherapies. In virotherapy, a relatively small amount of viruses used in an intratumoral injection preferentially replicate in and lyse cancer cells, leading to the release of amplified viral particles that spread the infection to the surrounding tumor cells and reduce the tumor mass. Adenoviruses (Ads) are most commonly used for oncolytic virotherapy due to their infection efficacy, high titer production, safety, easy genetic modification, and well-studied replication characteristics. Ads with deletion of E1b55K preferentially replicate in and destroy cancer cells and have been used in multiple clinical trials. H101, one of the E1b55K-deleted Ads, has been used for the treatment of late-stage cancers as the first approved virotherapy agent. However, the mechanism of selective replication of E1b-deleted Ads in cancer cells is still not well characterized. This review will focus on three potential molecular mechanisms of oncolytic replication of E1b55K-deleted Ads. These mechanisms are based upon the functions of the viral E1B55K protein that are associated with p53 inhibition, late viralmRNAexport, and cell cycle disruption.


Assuntos
Adenoviridae/fisiologia , Proteínas E1B de Adenovirus/deficiência , Vírus Oncolíticos/fisiologia , Replicação Viral , Adenoviridae/genética , Proteínas E1B de Adenovirus/genética , Deleção de Genes , Humanos , Vírus Oncolíticos/genética
8.
BMC Cancer ; 15: 716, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26475304

RESUMO

BACKGROUND: Clinical trials have indicated that preclinical results obtained with human tumor xenografts in mouse models may overstate the potential of adenovirus (Ad)-mediated oncolytic therapies. We have previously demonstrated that the replication of human Ads depends on cyclin E dysregulation or overexpression in cancer cells. ED-1 cell derived from mouse lung adenocarcinomas triggered by transgenic overexpression of human cyclin E may be applied to investigate the antitumor efficacy of oncolytic Ads. METHODS: Ad-cycE was used to target cyclin E overexpression in ED-1 cells and repress tumor growth in a syngeneic mouse model for investigation of oncolytic virotherapies. RESULTS: Murine ED-1 cells were permissive for human Ad replication and Ad-cycE repressed ED-1 tumor growth in immunocompetent FVB mice. ED-1 cells destroyed by oncolytic Ads in tumors were encircled in capsule-like structures, while cells outside the capsules were not infected and survived the treatment. CONCLUSION: Ad-cycE can target cyclin E overexpression in cancer cells and repress tumor growth in syngeneic mouse models. The capsule structures formed after Ad intratumoral injection may prevent viral particles from spreading to the entire tumor.


Assuntos
Adenocarcinoma/terapia , Ciclina E/biossíntese , Neoplasias Pulmonares/terapia , Terapia Viral Oncolítica , Adenocarcinoma/genética , Adenoviridae/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Ciclina E/genética , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Isoenxertos , Neoplasias Pulmonares/genética , Camundongos , Vírus Oncolíticos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cancer Biol Ther ; 15(9): 1256-67, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24972095

RESUMO

Epidemiological studies suggest that high intake of cruciferous vegetables is associated with a lower risk of cancer. Experiments have shown that indole-3-carbinol (I3C), a naturally occurring compound derived from cruciferous vegetables, exhibits potent anticarcinogenic properties in a wide range of cancers. In this study, we showed that higher doses of I3C (≥400 µM) induced apoptotic cancer cell death and lower doses of I3C (≤200 µM) repressed cancer cell growth concurrently with suppressed expression of cyclin E and its partner CDK2. Notably, we found that pretreatment with low doses of I3C enhanced Ad-mediated oncolysis and cytotoxicity of human carcinoma cells by synergistic upregulation of apoptosis. Thus, the vegetable compound I3C as a dietary supplement may benefit cancer prevention and improve Ad oncolytic therapies.


Assuntos
Adenoviridae , Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Indóis/farmacologia , Vírus Oncolíticos , Verduras/química , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Ciclina E/genética , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Sinergismo Farmacológico , Humanos
10.
Virol J ; 10: 293, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24059864

RESUMO

BACKGROUND: Combination of oncolytic adenoviruses (Ads) and chemotherapy drugs has shown promising therapeutic results and is considered as a potential approach for cancer therapy. We previously have shown that autophagy may generate decomposed cellular molecules that can be used as nutrition to support virus replication in cancer cells. In this study, we evaluated a unique combination of the novel oncolytic Ad-cycE with rapamycin, an autophagy inducer and first-line chemotherapeutic drug. METHODS: The combination of oncolytic Ad-cycE and the autophagy inducer rapamycin was assessed for enhanced antitumor effect. We also evaluated the combined effects of rapamycin and Ad-cycE on cancer cell viability. The interaction between Ad-cycE and rapamycin was analyzed with Calcusyn (Biosoft, Ferguson, MO). RESULTS: We show that rapamycin induces autophagy, enhances Ad E1A expression and increases Ad oncolytic replication. Combination of rapamycin and Ad-cycE elicits stronger cytotoxicity than single treatment alone. The analyzed data indicates that the Ad-cycE and rapamycin combination has a significantly synergistic antitumor effect. CONCLUSIONS: Our study provides a new insight into vector development and demonstrates the novel roles of autophagy in adenovirus replication. The combination of autophagy-induced chemotherapy and oncolytic virotherapy may be a new approach to improve future cancer treatment.


Assuntos
Adenoviridae/crescimento & desenvolvimento , Autofagia , Vírus Oncolíticos/crescimento & desenvolvimento , Sirolimo/metabolismo , Adenoviridae/fisiologia , Linhagem Celular , Sobrevivência Celular , Humanos , Carga Viral , Replicação Viral
11.
PLoS One ; 8(2): e57340, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23437375

RESUMO

Adenoviruses (Ads) with deletion of E1b55K preferentially replicate in cancer cells and have been used in cancer therapies. We have previously shown that Ad E1B55K protein is involved in induction of cyclin E for Ad replication, but this E1B55K function is not required in cancer cells in which deregulation of cyclin E is frequently observed. In this study, we investigated the interaction of cyclin E and CDK2 in Ad-infected cells. Ad infection significantly increased the large form of cyclin E (cyclin EL), promoted cyclin E/CDK2 complex formation and increased CDK2 phosphorylation at the T160 site. Activated CDK2 caused pRb phosphorylation at the S612 site. Repression of CDK2 activity with the chemical inhibitor roscovitine or with specific small interfering RNAs significantly decreased pRb phosphorylation, with concomitant repression of viral replication. Our results suggest that Ad-induced cyclin E activates CDK2 that targets the transcriptional repressor pRb to generate a cellular environment for viral productive replication. This study reveals a new molecular basis for oncolytic replication of E1b-deleted Ads and will aid in the development of new strategies for Ad oncolytic virotherapies.


Assuntos
Adenoviridae/genética , Ciclina E/genética , Quinase 2 Dependente de Ciclina/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Oncogênicas/genética , Proteína do Retinoblastoma/genética , Proteínas Virais/genética , Adenoviridae/metabolismo , Linhagem Celular Tumoral , Ciclina E/agonistas , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/virologia , Genes Reporter , Proteínas de Fluorescência Verde , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Proteínas Oncogênicas/agonistas , Proteínas Oncogênicas/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , RNA Interferente Pequeno/genética , Proteína do Retinoblastoma/antagonistas & inibidores , Proteína do Retinoblastoma/metabolismo , Roscovitina , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
12.
Virology ; 433(2): 538-47, 2012 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-23021422

RESUMO

Adenovirus-mediated gene transfer into a tumor mass can be improved by combining it with conditionally-replicating adenovirus (CRAd) when both vectors co-infect the same cancer cell. We investigated the efficiency of enhancing transgene expression and effectiveness of cancer killing of two advenoviruses (Ads), one expressing E2F-1 (AdE2F-1) and another expressing a truncated form of E2F-1 that lacks the transactivation domain (AdE2Ftr), when combined with oncolytic Adhz60. We found that AdE2F-1 with Adhz60 actually decreased E2F-1 expression and viral replication through a mechanism apparently involving repression of the cyclin-E promoter and decreased expression of early and late structural proteins necessary for viral replication. In contrast, AdE2Ftr with Adhz60 resulted in increased E2Ftr expression, AdE2Ftr replication, and cancer cell death both in vitro and in vivo. These results indicate that AdE2Ftr coupled with a CRAd enhances AdE2Ftr-mediated cancer cell death.


Assuntos
Adenoviridae/genética , Fator de Transcrição E2F1/genética , Neoplasias/terapia , Vírus Oncolíticos/genética , Adenoviridae/fisiologia , Proteínas E1A de Adenovirus/metabolismo , Animais , Morte Celular , Linhagem Celular Tumoral , Ciclina E/genética , Ciclina E/metabolismo , Regulação para Baixo , Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Terapia Viral Oncolítica , Vírus Oncolíticos/fisiologia , Regiões Promotoras Genéticas , Transdução Genética , Replicação Viral , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Cancer Biol Ther ; 13(12): 1195-204, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22892845

RESUMO

Melanoma is generally resistant to chemotherapy, which may be related to defects in death receptor signaling and to defects in induction of apoptosis. Forkhead family transcription factors induce the expression of death receptor ligands such as Fas ligand (Fas-L) resulting in apoptosis. We therefore investigated whether a triple mutant form of forkhead transcription factor FKHRL1 (FKHRL1/TM) can enhance Fas-L mediated-apoptosis in melanoma cells. Two melanoma cells A2058 or DM6 were tested for their sensitivity to agonistic anti-Fas antibody (CH-11); adenovirus expressing FKHRL1/TM (Ad-FKHRL1/TM) was assessed for its capability to induce activation of the caspase pathway; the role of Fas-L in the Ad-FKHRL1/TM mediated-cell death was also assessed in vitro. Ad-FKHRL1/TM antitumor activity in vivo was also evaluated in a mouse melanoma xenograft model. We found that DM6 melanoma cells were more resistant to Fas/Fas-L-mediated apoptosis induced by agonistic anti-Fas antibody than A2058 melanoma cells. Ectopic expression of FKHRL1/TM in melanoma cells upregulated Fas-L expression, decreased procaspase-8 levels, and significantly increased Fas/FasL-mediated cell death in both cells lines; this induced cell death was partially blocked by a Fas/Fas-L antagonist. Importantly, Ad-FKHRL1/TM treatment of subcutaneous melanoma xenografts in mice resulted in approximately 70% decrease in tumor size compared with controls. These data indicate that overexpression of FKHRL1/TM can induce the Fas-L pathway in melanoma cells. Ad-FKHRL1/TM therefore might represent a promising vector for melanoma treatment.


Assuntos
Apoptose/genética , Proteína Ligante Fas/metabolismo , Fatores de Transcrição Forkhead/genética , Melanoma , Adenoviridae , Animais , Sobrevivência Celular , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Melanoma/genética , Melanoma/metabolismo , Camundongos , Músculo Liso Vascular/citologia , Mutação , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Virology ; 416(1-2): 9-15, 2011 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21575980

RESUMO

Adenoviruses with deletion of E1b have been used in clinical trials to treat cancers that are resistant to conventional therapies. The efficacy of viral replication within cancer cells determines the results of oncolytic therapy, which remains poorly understood and requires further improvement. In this report, we show that adenoviruses induce autophagy by increasing the conversion of LC3-I to LC3-II and the formation of the Atg12-Atg5 complex. Inhibition of autophagy with 3-methyladenine (3MA) resulted in a decreased synthesis of adenovirus structural proteins, and thereby a poor viral replication; promotion of autophagy with rapamycin increased adenovirus yield. This study indicates that adenovirus-induced autophagy correlates positively with virus replication and oncolytic cell death, and that autophagy may generate nutrients that can be used for building viral progeny particles. These results further suggest that chemotherapeutic agents that increase cancer cell autophagy may improve the efficacy of oncolytic virotherapy.


Assuntos
Adenoviridae/fisiologia , Autofagia/fisiologia , Replicação Viral/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Proteínas E1B de Adenovirus/genética , Proteínas E1B de Adenovirus/metabolismo , Proteína 12 Relacionada à Autofagia , Proteína 5 Relacionada à Autofagia , Linhagem Celular Tumoral , Regulação Viral da Expressão Gênica , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo
15.
Cancer ; 116(18): 4420-32, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20549818

RESUMO

BACKGROUND: Adenovirus (Ad)-mediated E2F-1 gene transfer induces apoptosis in cancer cells in vitro and in vivo, but clinical application of E2F-1 in cancer gene therapy remains controversial because of the oncogenic potential of E2F-1. This barrier can be circumvented by using the truncated form of the E2F-1 gene (E2Ftr) (amino acids 1 through 375), which lacks the E2F-1 transactivation domain and cell cycle-promoting effects. METHODS: The authors constructed 3 adenoviral vectors that expressed E2Ftr under regulation of the tetracycline (Tet)-off system (AdTet-E2Ftr1, AdTet-E2Ftr2, and AdTet-E2Ftr3). These vectors were compared for E2Ftr expression and apoptosis induction in cancer cells and normal cells. E2Ftr antitumor activity in vivo also was assessed in a melanoma xenograft model. RESULTS: One of the 3 vectors, AdTet-E2Ftr3, had the highest E2Ftr protein expression levels, which were correlated with the greatest induction of apoptosis and inhibition of cancer cell growth. E2Ftr induced apoptosis in a variety of cancer cell lines independent of p53 status with little cytotoxicity in normal cell lines. In a mouse melanoma xenograft model, AdTet-E2Ftr3 exhibited an approximately 80% decrease in tumor size compared with controls in vivo. CONCLUSIONS: The current results indicated that AdTet-E2Ftr3 is a novel anticancer agent that has significant therapeutic activity in vitro and in vivo.


Assuntos
Adenoviridae/genética , Fator de Transcrição E2F1/genética , Terapia Genética/métodos , Vetores Genéticos , Neoplasias/terapia , Animais , Apoptose , Linhagem Celular Tumoral , Fator de Transcrição E2F1/química , Genes p53 , Camundongos , Camundongos Endogâmicos BALB C , Deleção de Sequência , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Chin J Traumatol ; 10(6): 381-4, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18045523

RESUMO

Splenosis is ectopic autotransplantation of splenic tissue after splenic trauma or surgery.(1) The most frequent locations are the surface of visceral peritoneum and parietal peritoneum. Liver and retroperitoneum are rarely involved.(1,2) We present here 2 cases of splenosis involving the liver and retroperitoneum with clinical information, imaging findings, and literature review.


Assuntos
Esplenose/diagnóstico , Abdome/diagnóstico por imagem , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Radiografia Abdominal , Tomografia Computadorizada por Raios X , Ultrassonografia
17.
Tumour Biol ; 28(2): 111-22, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17287612

RESUMO

OBJECTIVES: In the present study, we investigate the role of apoptosis signal-regulating kinase 1 (ASK1) mitogen-activated protein (MAP) kinase signal pathways in E2F-1-mediated apoptosis. METHODS: A gene expression profile in response to E2F-1 overexpression was performed by cDNA microarray analysis and confirmed by real-time reverse-transcription polymerase chain reaction. Kinase activities were assayed by Western blot analysis or kinase assay. Apoptosis was assessed by morphologic inspection and flow-cytometric analysis. Cytotoxicity was monitored by MTT assay. RESULTS: E2F-1 upregulated the expression of ASK1 8-fold compared to the Ad-LacZ-infected control in SK-MEL-2 melanoma cells, which was confirmed by reverse-transcription polymerase chain reaction. Sequence analysis showed that there are 2 putative E2F-1 DNA binding sites in the ASK1 promoter region. Truncated E2F-1 protein, which lacks the transactivation domain, failed to upregulate ASK1, suggesting that ASK1 was regulated at the transcriptional level by E2F-1. E2F-1 overexpression resulted in the transient activation of c-Jun N-terminal kinase (JNK); however, dominant negative mutant ASK1 had no effect on E2F-1 cytotoxicity and JNK activation. p38 was not activated by E2F-1, and inhibition of p38 had no effect on E2F-1-mediated cell death. The ASK1 kinase assay showed that ASK1 activity was not upregulated in response to E2F1 overexpression. The inhibition of ASK1 upstream kinase-AKT can enhance E2F-1-mediated cell death. Moreover, an adenovirus expressing truncated E2F-1 keeps the ability of inducing apoptosis in melanoma cells. CONCLUSIONS: ASK1 expression is upregulated by E2F-1 at the transcription level, but the upregulation of ASK1 expression by E2F-1 was not coordinated with an increased ASK1 activity. The ASK1-JNK/p38 pathway does not appear to play a crucial role in E2F-1-induced apoptosis.


Assuntos
Apoptose , Fator de Transcrição E2F1/metabolismo , Regulação Neoplásica da Expressão Gênica , MAP Quinase Quinase Quinase 5/metabolismo , Melanoma/metabolismo , Adenoviridae/genética , Adenoviridae/metabolismo , Fator de Transcrição E2F1/genética , Perfilação da Expressão Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinase 5/genética , Melanoma/genética , Melanoma/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Virology ; 350(2): 418-28, 2006 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-16542696

RESUMO

Adenoviruses with deletion of E1b gene can selectively replicate in cancer cells. The underlying mechanisms in tumor-selective replication of E1b-deleted adenoviruses are insufficiently understood. Identifying genes with altered expression patterns caused by the E1B proteins in virus-infected cells will further increase our understanding of E1B functions and provide insight into the tumor-selective replication of E1b-mutated adenoviruses on the molecular level. An approach based on large-scale gene array was applied to analyze molecular changes affected by viral E1B. We identified a total of 345 genes with expression changes of two-fold or greater affected by wild-type adenovirus compared with its E1b-deleted counterpart. The gene array data were confirmed by quantitative real-time PCR and Western blot. E1B proteins affect the expression of a diverse range of genes involved in cell cycle regulation, apoptosis, stress responses and angiogenesis. This is the first study of the global profile of gene expression altered by the viral E1B proteins in human lung cells, and the majority of the genes were previously not known to be affected by the viral proteins. The data presented in this study will lead to more detailed analysis of E1B functions and may also lead to development of new agents and approaches for oncolytic therapy.


Assuntos
Proteínas E1B de Adenovirus/genética , Perfilação da Expressão Gênica , Pulmão/virologia , Enzimas/genética , Regulação da Expressão Gênica , Humanos , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular/genética
19.
Breast Cancer Res ; 7(5): R580-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16168101

RESUMO

INTRODUCTION: Once metastasis has occurred, the possibility of completely curing breast cancer is unlikely, particularly for the 30 to 40% of cancers overexpressing the gene for HER2/neu. A vaccine targeting p185, the protein product of the HER2/neu gene, could have therapeutic application by controlling the growth and metastasis of highly aggressive HER2/neu+ cells. The purpose of this study was to determine the effectiveness of two gene vaccines targeting HER2/neu in preventive and therapeutic tumor models. METHODS: The mouse breast cancer cell line A2L2, which expresses the gene for rat HER2/neu and hence p185, was injected into the mammary fat pad of mice as a model of solid tumor growth or was injected intravenously as a model of lung metastasis. SINCP-neu, a plasmid containing Sindbis virus genes and the gene for rat HER2/neu, and Adeno-neu, an E1,E2a-deleted adenovirus also containing the gene for rat HER2/neu, were tested as preventive and therapeutic vaccines. RESULTS: Vaccination with SINCP-neu or Adeno-neu before tumor challenge with A2L2 cells significantly inhibited the growth of the cells injected into the mammary fat or intravenously. Vaccination 2 days after tumor challenge with either vaccine was ineffective in both tumor models. However, therapeutic vaccination in a prime-boost protocol with SINCP-neu followed by Adeno-neu significantly prolonged the overall survival rate of mice injected intravenously with the tumor cells. Naive mice vaccinated using the same prime-boost protocol demonstrated a strong serum immunoglobulin G response and p185-specific cellular immunity, as shown by the results of ELISPOT (enzyme-linked immunospot) analysis for IFNgamma. CONCLUSION: We report herein that vaccination of mice with a plasmid gene vaccine and an adenovirus gene vaccine, each containing the gene for HER2/neu, prevented growth of a HER2/neu-expressing breast cancer cell line injected into the mammary fat pad or intravenously. Sequential administration of the vaccines in a prime-boost protocol was therapeutically effective when tumor cells were injected intravenously before the vaccination. The vaccines induced high levels of both cellular and humoral immunity as determined by in vitro assessment. These findings indicate that clinical evaluation of these vaccines, particularly when used sequentially in a prime-boost protocol, is justified.


Assuntos
Vacinas Anticâncer , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/imunologia , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Animais , Linhagem Celular Tumoral , Feminino , Genes erbB-2/imunologia , Imunização Secundária , Interferon gama/biossíntese , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Metástase Neoplásica/imunologia , Metástase Neoplásica/prevenção & controle , Ratos , Sindbis virus/imunologia , Baço/imunologia
20.
Gene ; 344: 67-77, 2005 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-15656974

RESUMO

It has been shown that adenovirus-mediated overexpression of E2F-1 can efficiently induce apoptosis in cancer cells with little effect on normal cells. However, the mechanisms by which E2F-1 induces apoptosis remains poorly understood. The goal of this study was to evaluate changes in gene expression in response to E2F-1 in order to help elucidate the mechanisms by which E2F-1 causes apoptosis. Therefore, we used a quantitative microarray assay to identify the genes regulated by E2F-1 in melanoma cells. By gene expression profiling, we first screened a proprietary list of about 12,000 genes. Overexpression of E2F-1 in melanoma cells resulted in two-fold or greater alteration in the level of expression of 452 genes compared to vehicle-treated control cells. Most of the affected genes were not known to be responsive to E2F-1 prior to this study. E2F-1 adenoviral infection of these cells was found to affect the expression of a diverse range of genes, including oncogenes, transcription factors and genes involved in signal transduction, cell cycle regulation, cell proliferation and apoptosis, as well as other genes with unknown function. Changes in expression of 17 of these genes were confirmed by quantitative real-time polymerase chain reaction (PCR). This is first application of the microarray technique in the study of the global profile of genes regulated by E2F-1 in melanoma cells. This study leads to an increased understanding of the biochemical pathways involved in E2F-1-induced apoptosis and possibly to the identification of new therapeutic targets.


Assuntos
Apoptose/genética , Proteínas de Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Perfilação da Expressão Gênica , Fatores de Transcrição/fisiologia , Adenoviridae/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Análise por Conglomerados , Proteínas de Ligação a DNA/genética , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Vetores Genéticos/genética , Humanos , Melanoma/genética , Melanoma/patologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Transcrição/genética , Transfecção
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